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Otter dormouse
Order: Rodents (Rodentia) Family: Dormice (Gliridae) Habitat: southeast of Europe, valleys of rivers running into Fourseas. The last congelation at the boundary of Holocene and Neocene in had radically changed the geography of Eurasia. The glacier had moved huge masses of the ground as if huge “bulldozer” and has changed the direction of current of European rivers. Only the lower reaches of Dnepr, Don and Volga rivers had remained approximately in the same places, as in human epoch. But their upper courses are already absolutely different, rather than in human epoch. Number of inhabitants of European fresh waters had been reduced in great degree, and many fish-eating animals had died out. In particular, European otters were among them. Earlier their number was undermined by people, and it was an additional factor caused their extinction. After glacier thawing in early Neocene, when fresh waters of Europe had returned to the territory occupied earlier and had formed new river channels. In rivers freshwater fishes and crustaceans had settled again, but otters did not hunt them any more – they had died out irrevocably. However, such favourable ecological niche has not remained empty - rodents had undertaken a role of fish-eating river predator. It is remarkable, that in South America about the same situation had taken place in parallel and independently, but the descendant of completely another animal became aquatic predator there. And in Europe the role of Neocene “otter” is played by the descendant of fat dormouse (Glis glis), by otter dormouse. It is rather large rodent: it is approximately equal to marten in size. Top side of body of this animal is gray-brown; throat, breast and stomach are milky-white. Fur is very dense and rich; animal spends a lot of time looking after it and greases it regularly with fatty secretions of special glands. Head of otter dormouse is pointed, ears are small, and muzzle is lengthened. On muzzle there are very much advanced rigid and long vibrissae, helping to be guided even in muddy water. The basic body of underwater movement represents hind legs with long toes between which membranes are advanced. In addition this rodent swims with the help of wide and flattened tail similar a little to beaver’s tail. Forepaws are shorter, rather than hind ones, and at movement they are pressed against chest. Fingers lack of membranes, but the claws are advanced, and finger pads are very sensitive. The basic food of this rodent includes fish catching by otter dormouse in thickness of water. Occasionally it eats large crustaceans – crayfishes and large scuds. This rodent kills small prey (small crustaceans, tadpoles, fish fry and insects) by bite and hides in cheek pouches. Having emerged on surface of water, otter dormouse eats the saved up prey. Otter dormouse eats large fish on land, holding food in forepaws. Otter dormice live in clans, forming small settlements on riverbanks. Such colony totals up to ten adult animals, and also some individuals of young growth of the present year. “Lair” is arranged in holes in riverbanks. Holes are located no farther than one meter from each other; the single rodent and growing up posterity till some time lives in each one. Occasionally among otter dormice the convinced singles appear. They are less conservative in a choice of refuge and sometimes settle even in hollows of trees or in nests of large birds, arranging “ground floor” under nest (due to tenacious claws this rodent is able to climb up trees). But life alone for this rodent is rather compelled circumstances, than a rule. But the clan of these animals represents simply some individuals living nearby from each other and not connected with relationships in the majority. At them the hierarchy constructed by a principle of strict matriarchy is established: females are larger than males and settle in the center of colony. During the hunting each rodent operates separately and does not miss an opportunity to steal prey at weaker individual. Therefore the young growth, leaving mother, stays in colony rather seldom, especially if the place is not too rich in food. The only thing uniting these rodents is the danger. Even large wide-headed catfishes are afraid to attack group of these rodents, preying only young or single animals. Otter dormice have voice and can utter some different signals based on whistle. Loud whistle is, perhaps, a sound most important for them – it’s a signal of threat from air: birds of prey are usual enemies of these rodents. Rolling chirring is a signal of underwater alarm. At occurrence of a stranger from other clan, or a single individual, old residents of colony meet it with sibiliant whistle, accompanying it with threating poses. If the shortage of food takes place, otter dormice may be aggressive to strangers. Despite of descending from dormice, these rodents keep activity in winter. They punch thin ice on river surface with claws or gnaw it through. But usually in habitats of these rodents river does not become covered by ice – otter dormice do not settle far to the north. Two times per one year the female gives rise up to 5 – 6 cubs. They come into the world blind, but covered with wool. The first litter is born when winter colds have not passed yet, and the second litter appears in the middle of summer. Shortly before it female banishes the previous posterity. At one-year-old age young animals begin able to bring posterity. = by AlexSone = Category:Fandom Category:Animals Category:Mammals Category:Rodents